The Mexican government scored a public relations coup when it bloodlessly captured Zeta leader Miguel Angel Trevino Morales on Monday. But the long-term effects of the capture of the 40-year old man who was arguably the country's most brutal drug lord will likely lead to more, not less, violence.

The arrest sent out two messages that have ominous implications here. First, the blow to the head of the Zeta cartel signals internal and external rivals that the cartel is dazed and vulnerable to attack. This leads to surges in homicides, as the battle to control trafficking routes and illegal trade affects not only cartel members but local citizens and security forces as well.

How organised crime responds to a blow like this has nothing to do with the government narrative of good guys against bad guys. It causes a shake up and resettling that can reduce violence in some places where another cartel achieves undisputed control, and produce violence in places where turf wars flare up. It causes corrupt government forces to realign and often participate actively in the turf wars. It does not, however, lead to the elimination of drug trafficking or organised crime.

Everything we know from seven years of drug war points to the likelihood of more violence due to this trigger effect. The Mexican and US governments both acknowledge that what is known as "the kingpin strategy"- taking out drug lords -provokes violence.

Now with less central control in the Zetas, we can expect not only more infighting, but increased incursions into illegal activities beside drug trafficking - kidnapping, extortion, preying on migrants, sex trafficking and others that do immeasurable harm to their victims, to families and to communities.

They also know it doesn't work. Although in some cases a specific cartel could be fragmented or even knocked out of the game, with some $38bn in tax-free income at stake as it is in the sale of prohibited drugs to the US, people will find a way to keep up the business.

In the case of Trevino Morales, the Mexican press reports that he ran the Zetas with his brother, Omar, who remains at large and will presumably continue. Mexican authorities did not respond to questions about Omar taking on leadership, saying it is an investigation in progress. But even the director of the US Drug Enforcement Agency in Dallas, Texas noted after the arrest, "What it means is there are going to be plenty of people who take his place".

Even weakening the command center of a criminal group, presented as a major victory in the arrest of Trevino, often has negative effects on public safety. Central control within the Zetas has never been as consolidated as in other cartels. This meant a lack of any code of ethics, which sounds like an oxymoron in reference to criminal groups but functioned for years to restrain Mexican cartels from having much involvement in high profile, anti-social activities beyond the drug trade.

Now with less central control in the Zetas, we can expect not only more infighting, but increased incursions into illegal activities beside drug trafficking - kidnapping, extortion, preying on migrants, sex trafficking and others that do immeasurable harm to their victims, to families and to communities.

Despite all these concerns, the US government immediately congratulated the Pena Nieto government on the bust. It has supported the Mexican drug war with equipment, training and US agents on the ground and pressured the new Mexican president to continue the military/police model.

This is the second reason to fear a rise in violence. The Trevino Morales arrest and US and Mexican government statements following it are a joint message that the drug war will continue with support from both administrations - despite its failures and growing citizen opposition.

President Pena Nieto had attempted to put distance between his policies and the drug war of his predecessor, Felipe Calderon - and with good reason. The offensive on drug cartels with the deployment of the armed forces and police has led to more than 100,000 deaths in the country and widespread human rights violations. Drug trafficking has continued unabated and polls show most Mexicans see no progress in the campaign against drug traffickers.

Pena Nieto promised to redirect efforts from the drug war to public safety as a cornerstone of the campaign that brought him to office in July 2012.

This explains why this arrest was handled much differently from the past. If before criminals were brought out bloodied and cuffed with great fanfare, this time the administration sent out a discreet statement with mug shots of Trevino Morales, his two companions, and a map of where they were captured by Navy and police forces. Videos showed Trevino being led without handcuffs.

Eduardo Sanchez, the spokesperson for the security cabinet, noted that the alleged criminals were charged with "organised delinquency, murder, crimes against health (drug trafficking), torture, money laundering, illegal possession of arms, among others". He added the assassination of 265 migrants in San Fernando, Tamaulipas in two incidents that shocked Mexican society and the world. The self-congratulatory tone and combative talk of defeating organised crime was conspicuously absent.

Mexican security cabinet spokesman Eduardo Sanchez highlighted Mexican inter-agency cooperation. He dodged the question on US involvement in Trevino Morales' capture. The New York Times, citing anonymous sources, said the US government "played a key behind-the-scenes role" and helped confirm the identity of the drug lord through DNA.

Obama on the other hand, welcomed the news as a confirmation of Pena Nieto's commitment to the joint drug war. President Obama said in an interview with the Spanish-language Univision, "I think what it [the arrest of Trevino Morales] shows is that the Pena Nieto administration is serious about continuing efforts to interrupt drug operations". The network interpreted the short interview as a major endorsement of Pena Nieto's continued commitment to US-backed counternarcotic efforts.

Obama stated explicitly that there were questions about that commitment during the campaign. Indeed, US-Mexico cooperation in the drug war has hit rocky times. In addition to early fears that Pena Nieto would attempt to pact with the cartels, his decision to channel all security cooperation through the Ministry of the Interior - a move to rein in US agencies' open access to Mexican national security - caused concern in Washington.

Insiders said security assistance was on hold until the picture cleared. This move marks continued access and cooperation for US government agents under the same drug war model, just when questions about the cooperation are again emerging in light of leaks that Mexico is among countries routinely spied on by the US National Security Agency.

The US government is heavily invested in the Mexican drug war, not so much due to the more than $2bn dollars it has spent to bolster the disastrous strategy, but in the enormous expansion of its presence in Mexico. The US security aid package known as the Merida Initiative allowed many US government agencies to more than double their personnel under a broad umbrella that places US agents in intelligence-gathering, counternarcotic operations, border control and spying. It represents millions of dollars in contracts to private defense, security and computer firms.

Assuming the crimes attributed to him are proven in a court of law, no one could fail to celebrate the incarceration of a cold-blooded criminal such as Miguel Angel Trevino Morales.

But that the arrest signals the continued alliance of the US and Mexican governments in a security effort that uses the public as collateral damage is bad news for us all.

Laura Carlsen is a policy analyst and director of the Americas Program of the Center for International Policy. She is based in Mexico City. Her writings can be found at www.cipamericas.org